Conversion of aromatic ring compounds into motor spirit



Patented Dec. 26, 1922 ALEXANDER S. RAMAGE, OF DETROIT, MICHIGAN,ASSIGNOR T FRANK I. IBEA LL, ALEXANDER S. JBAMAGE, BENJAMIN BRISCOE, ALLOF DETROIT, MICHIGAN, TRUSTEES, KNOWN AS CHEMICAL RESEARCH SYNDICATE,LTD.

CONVERSION OF ABGH ATIG RING COMPOUNDS INTO MOTOR SPIRIT.

Drawing.

To all whomit may concern; 7

Be it known that I, ALEXANDER S..RAu- AGE, a. citizen of the UnitedStates, residing at Detroit, in the county of Wayne and State 5 ofMichigan, have invented certain new and useful Improvements in theConversion of Aromatic Ring Compounds into Motor ge Spirit, of which thefollowing is a specification.

The object of this invention is to form a low-boiling point motor spiritconsisting mainly of compounds of the saturated ring type, such as thecycloparaflins. Under the conditions of use in internal combustionengines the compounds of the olefin type very rapidly polymerize 'withthe formation of resinous compounds which tend to gum the valves; andthis same effect has been found to exist even with motor spirits of theparaffin type.

Experience has shown that the least decomposable motor spirit is thatcontaining cyclohexane. M

It has been shown by Sabatier that cyclohexane isformed when benzol ishydrogenated by passing the vapors of benzol and hydrogen over a nickelcatalyzer at 200 C.

I have discovered that this cycloh'exane is i more readily formed byexposing the vapors of benzol or like compounds under suitable heatconditions to the action of highly reactive hydrogen, nerated by achemical reaction taking pl a iie in resence of the body to behydrogenated. preferred reac- 85 tion for the generation of hydrogen isthat of steam upon ferrous oxid at temperatures above 550 C. In thepreferred embodiment of my invention the ferrous oxid is continuouslyregenerated by a reducing reaction in- 40 volving the ferric oxid and ahydrocarbon gas or vapor other than the aromatic compound tobehydrogenated. 4

In carrying out my invention in its preferred embodiment I mix witharomatic compounds such as benzene, toluene, xylene,

etc, and their homologues, a parafiin or olefin hydrocarbon, and passthe mixture in vapor form, together with superheated steam, over ferrousoxid or a similar suboxid capable of decomposing steam, kept at atemperature between 550700 C.

The principal reactions which may be in- Application filed January as,1921. Serial in. 440,744.

volved in the practice of my process are expressed as follows: l

l. The oxidation of ferrous oxid to ferric oxid by means of steam at atemperature of from 550 C. to 650 C. with generation of highly reactiveor so-called nascent hydro- 2. The dehydrogenation of saturatedhydrocarbon compounds to unsaturated compounds by means of ferric oxid.

3. The splitting up of the unsaturated compounds at high temperatures,of say 650 0., into simpler hydrocarbons such as ethylene.

4. That ethylene or other hydrocarbon gases including methane react withferric oxid at temperatures of 500 C. to 550 C. yielding ferrous oxid,carbon, and water.

5. That at temperatures of 500 C. to 600 C. carbon reduces ferric oxidto ferrous oxid with formation of carbon monoxid.

6. That at similar temperatures or under, carbon monoxid reduces ferricoxid to ferrous oxid with formation of carbon dioxid.

7. That at 500 C. water is decomposed by ferrous. oxid with theformation of ferric oxid and hydro n. 8. That the hy rogen thus producedread- 11y replaces the methyl group, and carries on the hydro enation upto the. formation of cyclopara ns.

This process is very applicable to the oils distilled from coal, or cokeoven tars, as these already contain the mixture of paraffins andaromatic hydrocarbons.

It will be understood that these reactions. are occurring simultaneouslyor in succession. Thus upon the introduction of su rheated steam and theheavy hydrocar 11 into a retort containing ferrous oxid the ferrous oxidis oxidized to ferric oxid according to the reaction:

Thereupon a reaction which for a specific case chosen for illustrationmay be expressed as follows, occurs.

This reaction occurs at from 450-500 C. At higher temperatures as from650700 C. the compounds represented by the formula C H will bedecomposed into 7 parts of ethylene C IL.

The reaction between ethylene and ferric oxid and other simultaneous orsuccessive reactions may be:

When 20 molecules of water are added there results:

Therefore from 198 pounds of C H and 360 pounds of steam there isproduced pounds of nascent hydro en. This amount is suiiicient tocompletey hydro nate to a 'cycloparaffin compound, 10 mo ecules ofbenzene or 7 molecules of toluene or 6 molecules of xylene or 5molecules of mesitylene and cumene. Of course ethylene can be usedinstead of a parafiin, such as C H using the proportions as designatedin the equations. The equations representing the h'ydrogenating efiectupon the aromatic compounds may be represented as follows:

In every case some of the C,H, polymer'zes to (LH and (1,,H because thefinal pro uct contains these compounds to the extent of 10 to 20%.

In the practical operation of the process the mixture of aromatic andparaflin or olefin compounds,'such as the vapors from coal tar, isintroduced together with a definitely determined quantity of steam intoa preferably slightly inclined 4;" diameter tube 20 long containingferrous oxid. The tube is fitted at the entrance end with an orificevalve (a gate valve with a orifice drilled through the valve) for thedelivery of the oil vapors, and also with a gate valve with a orificefor the superheated steam. With an oil and steam pressure of 10 poundson the one side, and practically none on the tube side, these valvesadmit exactly 5 gallons of oil and 8 pounds of steam per hourrespectively. As the boiling point of theoil in the vaporizing stillrises the amount of steam can be increased by raising the pressure asthe temperature rises. The temperature of the tube at the up er orentrance end is kept at about 600 the temperature gradually increasingto about 700 C. at the outlet end.

As a result of the reactions within the tube there is produced a mixtureof vapors and gases, which, upon condensation, yield a motor spiritentirely free from water and composed principall of cyclohexane (boilingat about 81 together with light paraflins, some cyclo-olefins andcyclo-paraffins, and also some unchanged aromatics as benzene and itshomologues. Such a product is obtained from ordinary coal or coke oventars which contain mixtures of aromatic com ounds, paraflins andolefins.

hen the process is carried out under the conditions stated no water assuch is found in the condensate. It is important that the steam bealways used in the required proportions. Otherwise, if an excess ofsteam is used, too much FeO is oxidized and the reaction wouldultimately come to a cessation. It is preferable therefore not to usemore steam than is requisite theoretically to carry out the reaction.After a run 0 24 hours, a sample of the oxid drawn from the tube shouldupon analysis contain neither carbon nor ferric oxid.

It is also essential that the ferrous oxid should not be reduced tometallic'iron, since in the presence of iron, carbon is deposited fromthe oil-vapors.

1. The continuous process of hydrogenating hydrocarbons consistingessentia 1y of aromatic bodies which comprises passing the hydrocarbonsin vapor form, admixed with another non-aromatlc hydrocarbon and withsteam, in contact with an iron compound substantially maintained in astate of ferrous oxid, at an elevated temperature not below 550 C. o

2. The continuous process of hydro nating hydrocarbons consistingessentia ly of aromatic bodies which comprises sub'ecting thehydrocarbons in vapor form, ixed with another non-aromatic hydrocarbonand with steam to the action of ferrous oxid at an elevated temperaturenot substantially below 550 (1., and regulating the proportion of steamto h drocarbon to maintain the oxid substantia ly in the ferrous state.

In testimony whereof, I afiix my signature.

ALEXANDER S. RAMAGE.

